Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

To: Jason Gunthorpe <jgg@xxxxxxxxxx>
Subject: Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
From: Christoph Hellwig <hch@xxxxxx>
Date: Wed, 6 Apr 2022 17:47:23 +0200
Cc: Christoph Hellwig <hch@xxxxxx>, Alex Williamson <alex.williamson@xxxxxxxxxx>, Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>, Christian Benvenuti <benve@xxxxxxxxx>, Cornelia Huck <cohuck@xxxxxxxxxx>, David Woodhouse <dwmw2@xxxxxxxxxxxxx>, Gerald Schaefer <gerald.schaefer@xxxxxxxxxxxxx>, iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx, Jason Wang <jasowang@xxxxxxxxxx>, Joerg Roedel <joro@xxxxxxxxxx>, kvm@xxxxxxxxxxxxxxx, linux-arm-kernel@xxxxxxxxxxxxxxxxxxx, linux-arm-msm@xxxxxxxxxxxxxxx, linux-rdma@xxxxxxxxxxxxxxx, linux-s390@xxxxxxxxxxxxxxx, Matthew Rosato <mjrosato@xxxxxxxxxxxxx>, "Michael S. Tsirkin" <mst@xxxxxxxxxx>, Nelson Escobar <neescoba@xxxxxxxxx>, netdev@xxxxxxxxxxxxxxx, Rob Clark <robdclark@xxxxxxxxx>, Robin Murphy <robin.murphy@xxxxxxx>, Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>, virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx, Will Deacon <will@xxxxxxxxxx>, "Tian, Kevin" <kevin.tian@xxxxxxxxx>
In-reply-to: <20220406141446.GE2120790@nvidia.com>
References: <0-v1-ef02c60ddb76+12ca2-intel_no_snoop_jgg@nvidia.com> <1-v1-ef02c60ddb76+12ca2-intel_no_snoop_jgg@nvidia.com> <20220406053039.GA10580@lst.de> <20220406120730.GA2120790@nvidia.com> <20220406135150.GA21532@lst.de> <20220406141446.GE2120790@nvidia.com>
User-agent: Mutt/1.5.17 (2007-11-01)

On Wed, Apr 06, 2022 at 11:14:46AM -0300, Jason Gunthorpe wrote:
> Really? It is the only condition that dma_info_to_prot() tests to
> decide of IOMMU_CACHE is used or not, so you are saying that there is
> a condition where a device can be attached to an iommu_domain and
> dev_is_dma_coherent() returns the wrong information? How does
> dma-iommu.c safely use it then?

arm does not use dma-iommu.c

Follow-Ups:
- Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
  - From: Jason Gunthorpe

References:
- [PATCH 0/5] Make the iommu driver no-snoop block feature consistent
  - From: Jason Gunthorpe
- [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
  - From: Jason Gunthorpe
- Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
  - From: Christoph Hellwig
- Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
  - From: Jason Gunthorpe
- Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
  - From: Christoph Hellwig
- Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
  - From: Jason Gunthorpe

Prev by Date: Re: [PATCH V9 4/6] regulator: Add a regulator driver for the PM8008 PMIC
Next by Date: Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
Previous by thread: Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
Next by thread: Re: [PATCH 1/5] iommu: Replace uses of IOMMU_CAP_CACHE_COHERENCY with dev_is_dma_coherent()
Index(es):
- Date
- Thread

[Index of Archives] [Linux ARM Kernel] [Linux ARM] [Linux Omap] [Fedora ARM] [Linux for Sparc] [IETF Annouce] [Security] [Bugtraq] [Linux MIPS] [ECOS] [Asterisk Internet PBX] [Linux API]